MEMS acoustic transducer with combfingered electrodes and corresponding manufacturing process

A MEMS acoustic transducer provided with: a substrate of semiconductor material, having a back surface and a front surface opposite with respect to a vertical direction; a first cavity formed within the substrate, which extends from the back surface to the front surface; a membrane which is arranged at the upper surface, suspended above the first cavity and anchored along a perimeter thereof to the substrate; and a combfingered electrode arrangement including a number of mobile electrodes coupled to the membrane and a number of fixed electrodes coupled to the substrate and facing respective mobile electrodes for forming a sensing capacitor, wherein a deformation of the membrane as a result of incident acoustic pressure waves causes a capacitive variation of the sensing capacitor. In particular, the combfingered electrode arrangement lies vertically with respect to the membrane and extends parallel thereto.